I think the correct answer is: C) Deepen a poem's meaning.
Allusion refers to a brief and indirect fererence to a person, a place, a thing or an idea. They are based on the assumption that most of people share a specific body of knowledge, in that way the reader undestands that reference. In that way a short allusion may lead the reader to a much deeper theme, like mithology or the bible, the poem has now a conection with something else. Sometimes the reader will understand the allusion and sometimes he won't. By making a research he will be able to understand and the poem will have a diferent of deeper mening.
the difference about the theme of "discovery" that william bradford and robert frost both explore are: about their way to travel of what they choosing or made as the goal their explorer.
Yes, the ideal that every US citizen should have an equal opportunity to achieve success. Through prosperity, through hard work, determination, and initiative.